COVID vaccine is good for at least 6 months but a booster might be needed after that Melissa Correa COVID vaccine is good for at least 6 months but a booster might be needed after that Replay Video UP NEXT Houston hospital leaders said they’re tracking an increase in COVID-19 cases and hospitalizations, even though the City of Houston Health Department reports the positivity rate for COVID-19 has leveled off. The doctors said more children are spreading the virus. The CDC is now looking at the link between the spread and extracurricular activities. They said the highly contagious UK coronavirus variant is also helping to drive up cases.